3-year clinical effectiveness of one-step adhesives in non-carious cervical lesions.

OBJECTIVES: Despite representing an important component of current dental adhesives, HEMA has been said to negatively influence the long-term stability of adhesion to dentine and enamel. The aim of this randomised clinical trial was to evaluate the 3-year clinical performance of two one-step self-etch adhesives. METHODS: Thirty patients had 175 non-carious cervical lesions restored with composite (Gradia Direct Anterior, GC) using either the HEMA-rich adhesive Clearfil Tri-S Bond (C3S; Kuraray) or the HEMA-free adhesive G-Bond (GB; GC). The restorations were evaluated by two examiners at baseline, 6, 12, 24 and 36 months regarding retention, caries recurrence, marginal integrity and discoloration and post-operative sensitivity. The data were statistically analysed with GEE and McNemar tests (p<0.05). RESULTS: The recall rate at 6 and 12 months was 100% and decreased to 96.7% at 24 and 36 months. At 3 years, the retention rate was 93.8% for C3S and 98.8% for GB (p=0.14). A pairwise comparison showed no significant differences between the two adhesives for all the parameters evaluated, irrespective of the recall (p>0.05). After 3 years, both adhesives presented an increase in the percentage of clinically acceptable marginal discoloration (C3S: 32.9% and GB: 26.8%) normally associated to clinically acceptable marginal defects (C3S: 35.8% and GB: 26.5%). Only 1 dentine margin of a GB restoration presented a severe marginal defect (1.2%) and 1 C3S restoration presented caries recurrence. The overall 3-year clinical success rate was 92.6% for C3S and 97.6% for GB (p=0.16). CONCLUSION: Both one-step self-etch adhesives presented an equally favourable clinical effectiveness at 3 years. CLINICAL SIGNIFICANCE: HEMA is a monomer frequently present in dental adhesives in order to increase their wettability and hydrophilicity. However, this monomer negatively influences hydrolytic stability and durability of the adhesive interface complex. In this 3-year clinical trial no significant difference in bonding effectiveness was noticed between a HEMA-rich and HEMA-free one-step adhesive.

Physical-mechanical properties of glass ionomer cements indicated for atraumatic restorative treatment.

BACKGROUND: This study evaluated mechanical properties of glass ionomer cements (GICs) used for atraumatic restorative treatment. Wear resistance, Knoop hardness (Kh), flexural (F(s)) and compressive strength (C(s)) were evaluated. The GICs used were Riva Self Cure (RVA), Fuji IX (FIX), Hi Dense (HD), Vitro Molar (VM), Maxxion R (MXR) and Ketac Molar Easymix (KME). METHODS: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. F(s), C(s), and Kh were analysed with one-way ANOVA. RESULTS: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F(s) and C(s), KME, FIX and HD had the best performance. Strong explanatory power between F(s) and the Kh (r(2) = 0.85), C(s) and the Kh (r(2) = 0.82), long-term wear and F(s) of 24 h (r(2) = 0.79) were observed. CONCLUSIONS: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear.

Bonding effectiveness of different adhesion approaches to unground versus ground primary tooth enamel.

AIM: This study aims to evaluate the bonding effectiveness of self-etch and etch-and-rinse adhesive systems in on intact and ground primary tooth enamel. STUDY DESIGN: Sixty primary incisors were divided into 6 groups according to the adhesive system (etch-and-rinse - Adper Single Bond 2 - SB, 2 steps self-etch -Clearfil SE Bond - SE, and 1 step self-etch - One Up Bond F Plus OBF) and to the substrate (ground or intact enamel): G1-SB/intact enamel; G2-SE/intact enamel; G3- OBF/intact enamel; G4-SB/ground enamel; G5- SE/ground enamel and G6-OBF/ground enamel. METHODS: Microshear bond test specimens were prepared with microhybrid composite and after 24h of water storage the microshear test was performed. STATISTICS: Data were submitted to statistical analysis using two-way ANOVA and Tukey's tests (p<0.05). RESULTS: Comparing the enamel characteristics (ground or intact) only when SE was used a statistically significant difference was found, as G2 (21.12+/-4.52) was statistically lower than G5 (33.29+/-5.44). Among the intact enamel groups, SB (26.11+/-7.56) was statistically superior to SE (21.12+/-4.52) and OBF (17.01+/-3.96). However, when comparisons were made among groups of ground enamel, SE (33.29+/-5.44) was significantly higher than SB (26.35+/-8.18) and OBF (17.52+/-3.46). CONCLUSION: The two-step self-etch adhesive system is a reliable alternative to etch and rinse adhesive systems on both ground and intact primary enamel.